Updating to LabQuest Viewer 1.1 or newer will resolve this issue.
There are a few known reasons why this could happen:
1) Apple Bonjour isn’t installed/running.
– Go into the Windows Control Panel and select “Add/Remove Programs” (XP) or “Programs” (Vista&7) and uninstall “Bonjour”.
– Reinstall the LabQuest Viewer.
2) Microsoft .NET framework is out of date or missing.
-Run Windows Update and install all recommended updates. -Look though the list of optional updates and install any involving Microsoft .NET. Keep in mind that if you haven’t run Windows Update in a while you may need to run it multiple times, (until it doesn’t find anything new,) as it will upgrade a component, and then applies patches on top of the upgrade.